My main comment is that it is a very lucid statement and I agreed with all of it. Perhaps I would stress even more strongly
(if that is possible) how futile is the argument without more theoretical clarity about mechanisms. No empirical study is
going to be generalizable or otherwise useful if it doesn't rest upon, or itself clear up, understanding of mechanism

One approach to PPT is neutrality of health efforts -- namely that the health impact of all costs (including opportunity cost)
of regulation to [ . . . ] not exceed the imputed dys[ . . .]fit of exposure to the same.

Yours,

Joshua.

[END PAGE ONE]

[BEGIN PAGE TWO]

P.D.

[stamped, APR -- 6 1981]

P.S.

I would like to think of a way to pursue this promising lead to be able to make a stronger etiological statement than "appears
to be involved". (You did state this with appropriate caution.)